The invention relates generally to machines which require repositioning of a rotary tool with respect to a reference point on the machine.
More specifically, the invention relates to machine tools such as grinding and milling machines, which often employ at least two rotary tools, and where it is desirable to periodically vary the axial distance between the two tools.
On machines, such as a centerless grinder, similar parts may have the same diameters to be ground, but the ground diameters, or lands, may be of different axial dimension from one another within a given family of parts, such as hydraulic valve spools. Multiple grinding wheels are typically located on a common grinding wheel collet, received on the grinding spindle, and the collet makes use of ring-like spacers to spread the wheels. When it is necessary to vary the distance between the wheels, the collet may be replaced by an entirely different collet and wheel set up, or the collet must be dismantled to replace the spacer rings between the grinding wheels.
The aforesaid mentioned technique for varying the axial spread dimensions of grinding wheels proves to be cumbersome and costly in terms of parts required and in wheel set-up time.
Applicant has obviated the difficulties inherent in the tool usage for varying the axial spread dimension between a pair of rotary tools, such as grinding wheels, by a novel tool setup which provides for one wheel to be fully and easily adjustable with respect to the other wheel by a thread-like mechanism embodying nested conical springs to effect clamping and unclamping of the tool setup.
It is therefore an object of the present invention to provide for a tool holder which may be adjustably positioned on machine tool spindle in a quick and efficient manner.
Another object of the present invention is to provide for an adjustable rotary tool holder which embodies a spring mechanism to easily effect clamp and unclamp of the tool holder on the machine tool spindle.